// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.Diagnostics;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Internal;

namespace Microsoft.AspNetCore.SignalR.Tests
{
    public class VerifyMethodFilter : IHubFilter
    {
        private readonly TcsService _service;
        public VerifyMethodFilter(TcsService tcsService)
        {
            _service = tcsService;
        }

        public async Task OnConnectedAsync(HubLifetimeContext context, Func<HubLifetimeContext, Task> next)
        {
            _service.StartedMethod.TrySetResult(null);
            await next(context);
            _service.EndMethod.TrySetResult(null);
        }

        public async ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            _service.StartedMethod.TrySetResult(null);
            var result = await next(invocationContext);
            _service.EndMethod.TrySetResult(null);

            return result;
        }

        public async Task OnDisconnectedAsync(HubLifetimeContext context, Exception exception, Func<HubLifetimeContext, Exception, Task> next)
        {
            _service.StartedMethod.TrySetResult(null);
            await next(context, exception);
            _service.EndMethod.TrySetResult(null);
        }
    }

    public class SyncPointFilter : IHubFilter
    {
        private readonly SyncPoint[] _syncPoint;
        public SyncPointFilter(SyncPoint[] syncPoints)
        {
            Debug.Assert(syncPoints.Length == 3);
            _syncPoint = syncPoints;
        }

        public async Task OnConnectedAsync(HubLifetimeContext context, Func<HubLifetimeContext, Task> next)
        {
            await _syncPoint[0].WaitToContinue();
            await next(context);
        }

        public async ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            await _syncPoint[1].WaitToContinue();
            var result = await next(invocationContext);

            return result;
        }

        public async Task OnDisconnectedAsync(HubLifetimeContext context, Exception exception, Func<HubLifetimeContext, Exception, Task> next)
        {
            await _syncPoint[2].WaitToContinue();
            await next(context, exception);
        }
    }

    public class FilterCounter
    {
        public int OnConnectedAsyncCount;
        public int InvokeMethodAsyncCount;
        public int OnDisconnectedAsyncCount;
    }

    public class CounterFilter : IHubFilter
    {
        private readonly FilterCounter _counter;
        public CounterFilter(FilterCounter counter)
        {
            _counter = counter;
            _counter.OnConnectedAsyncCount = 0;
            _counter.InvokeMethodAsyncCount = 0;
            _counter.OnDisconnectedAsyncCount = 0;
        }

        public Task OnConnectedAsync(HubLifetimeContext context, Func<HubLifetimeContext, Task> next)
        {
            _counter.OnConnectedAsyncCount++;
            return next(context);
        }

        public Task OnDisconnectedAsync(HubLifetimeContext context, Exception exception, Func<HubLifetimeContext, Exception, Task> next)
        {
            _counter.OnDisconnectedAsyncCount++;
            return next(context, exception);
        }

        public ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            _counter.InvokeMethodAsyncCount++;
            return next(invocationContext);
        }
    }

    public class NoExceptionFilter : IHubFilter
    {
        public async Task OnConnectedAsync(HubLifetimeContext context, Func<HubLifetimeContext, Task> next)
        {
            try
            {
                await next(context);
            }
            catch { }
        }

        public async Task OnDisconnectedAsync(HubLifetimeContext context, Exception exception, Func<HubLifetimeContext, Exception, Task> next)
        {
            try
            {
                await next(context, exception);
            }
            catch { }
        }

        public async ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            try
            {
                return await next(invocationContext);
            }
            catch { }

            return null;
        }
    }

    public class SkipNextFilter : IHubFilter
    {
        private readonly bool _skipOnConnected;
        private readonly bool _skipInvoke;
        private readonly bool _skipOnDisconnected;

        public SkipNextFilter(bool skipOnConnected = false, bool skipInvoke = false, bool skipOnDisconnected = false)
        {
            _skipOnConnected = skipOnConnected;
            _skipInvoke = skipInvoke;
            _skipOnDisconnected = skipOnDisconnected;
        }

        public Task OnConnectedAsync(HubLifetimeContext context, Func<HubLifetimeContext, Task> next)
        {
            if (_skipOnConnected)
            {
                return Task.CompletedTask;
            }

            return next(context);
        }

        public Task OnDisconnectedAsync(HubLifetimeContext context, Exception exception, Func<HubLifetimeContext, Exception, Task> next)
        {
            if (_skipOnDisconnected)
            {
                return Task.CompletedTask;
            }

            return next(context, exception);
        }

        public ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            if (_skipInvoke)
            {
                return new ValueTask<object>();
            }

            return next(invocationContext);
        }
    }

    public class DisposableFilter : IHubFilter, IDisposable
    {
        private readonly TcsService _tcsService;

        public DisposableFilter(TcsService tcsService)
        {
            _tcsService = tcsService;
        }

        public void Dispose()
        {
            _tcsService.StartedMethod.SetResult(null);
        }

        public ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            return next(invocationContext);
        }
    }

    public class AsyncDisposableFilter : IHubFilter, IAsyncDisposable
    {
        private readonly TcsService _tcsService;

        public AsyncDisposableFilter(TcsService tcsService)
        {
            _tcsService = tcsService;
        }

        public ValueTask DisposeAsync()
        {
            _tcsService.StartedMethod.SetResult(null);
            return default;
        }

        public ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            return next(invocationContext);
        }
    }

    public class ChangeMethodFilter : IHubFilter
    {
        public ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
        {
            var methodInfo = typeof(BaseHub).GetMethod(nameof(BaseHub.BaseMethod));
            var context = new HubInvocationContext(invocationContext.Context, invocationContext.ServiceProvider, invocationContext.Hub, methodInfo, invocationContext.HubMethodArguments);
            return next(context);
        }
    }
}
